This section of our beginning python training class always stumps students.  Firstly, because they need to know the difference between a function and a method.  Secondly, they need to understand object oriented programming concepts.  Thirdly, they need to realize that python has three types of methods.  Then they need to know how to use each method, which means they need to know the purpose of each method type.  Then they have to understand mutable versus non-mutable types.  The list goes on.  As part of our python tutorial, I hope to shed some light on this confusing topic.

To begin, the difference between a function and a method in python is that a method is defined within a class.  Here is an illustration:

#function

	def greeting():
	                print "Hello, I hope you're having a great day!"

	class HSGPrinter(object):
	                #method
	                def greeting(self): 
	                                print "Hello, I hope you're having a great day!"

As should be obvious, the second definition of greeting is encapsulated within the HSGPrinter class and is , therefore, refered to as a method.

The astute reader will notice that the greeting method contains one parameter named self.  For those who know C++ , Java or C#, self is equivalent to this i.e. it is a reference to the invoking object:

The RSS feed, which commonly stands for Really Simple Syndication, is an internet protocol that helps spread the availability of frequently published or updated Internet content.

RSS Benefits for an Internet Content Provider or Blogger
The use of an RSS feed saves immeasurable time for a content provider. When an interested person subscribes to an RSS feed, the owner of that feed now has a way to reach large numbers of people without having to resort to spamming techniques. The RSS feed also allows a content provider to send the requested topical information without specifically asking, every time, to those people who have subscribed. The content provider uses a program, written in XML code to make the information they post available to each person that has requested a subscription to that particular RSS feed.

RSS Benefits for the Average Internet User
The Internet grows larger by the minute. It is easy for a person to have information overload. The use of an RSS feed gives an individual more control over what information they see while on the Internet. It is also very useful for anyone that wants to stay up to date. Subscribing to the RSS feed for a topic of interest automatically provides the subscriber continued availability of the latest information on that topic. The Internet user relies on a small program called an RSS Feeder to gather the information on the RSS feeds to which they have subscribed.

Most browsers these days have built in RSS readers making that gathering the desired information easier than ever to accomplish. Joining an RSS feed is a very simple thing to accomplish.
 

RSS Benefits for Small Businesses

More and more Small Business owners are adapting targeted online marketing campaigns such as RSS Feeds in order to provide relevant content to new and existing customers. Maintaining web content such as:  company news; contests; promotional events; related articles; notifications; product launches; directories; and newsletters are examples of ways of staying in touch with customers in any niche market.  As search engines retrieve information from RSS Feeds and content is syndicated to other websites, chances of increased traffic are inevitable.  For active websites, RSS feeds are invaluable tools for small business owners.

USA.gov Updates: News and Features

Search for RSS feeds (search topics)

Welcome to Google Reader (find and keep track of interesting stuff on the web.)

NPR public radio station (popular, news, program and topics RSS feeds)

RSS in Plain English (video)

10 Helpful Uses of RSS Feeds for Marketing

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Adding RSS Content on Yahoo

Python and Ruby, each with roots going back into the 1990s, are two of the most popular interpreted programming languages today. Ruby is most widely known as the language in which the ubiquitous Ruby on Rails web application framework is written, but it also has legions of fans that use it for things that have nothing to do with the web. Python is a big hit in the numerical and scientific computing communities at the present time, rapidly displacing such longtime stalwarts as R when it comes to these applications. It too, however, is also put to a myriad of other uses, and the two languages probably vie for the title when it comes to how flexible their users find them.

A Matter of Personality...

That isn't to say that there aren't some major, immediately noticeable, differences between the two programming tongues. Ruby is famous for its flexibility and eagerness to please; it is seen by many as a cleaned-up continuation of Perl's "Do What I Mean" philosophy, whereby the interpreter does its best to figure out the meaning of evening non-canonical syntactic constructs. In fact, the language's creator, Yukihiro Matsumoto, chose his brainchild's name in homage to that earlier language's gemstone-inspired moniker.

Python, on the other hand, takes a very different tact. In a famous Python Enhancement Proposal called "The Zen of Python," longtime Pythonista Tim Peters declared it to be preferable that there should only be a single obvious way to do anything. Python enthusiasts and programmers, then, generally prize unanimity of style over syntactic flexibility compared to those who choose Ruby, and this shows in the code they create. Even Python's whitespace-sensitive parsing has a feel of lending clarity through syntactical enforcement that is very much at odds with the much fuzzier style of typical Ruby code.

For example, Python's much-admired list comprehension feature serves as the most obvious way to build up certain kinds of lists according to initial conditions:

a = [x**3 for x in range(10,20)]
b = [y for y in a if y % 2 == 0]

first builds up a list of the cubes of all of the numbers between 10 and 19 (yes, 19), assigning the result to 'a'. A second list of those elements in 'a' which are even is then stored in 'b'. One natural way to do this in Ruby is probably:

a = (10..19).map {|x| x ** 3}
b = a.select {|y| y.even?}

but there are a number of obvious alternatives, such as:

a = (10..19).collect do |x|
x ** 3
end

b = a.find_all do |y|
y % 2 == 0
end

It tends to be a little easier to come up with equally viable, but syntactically distinct, solutions in Ruby compared to Python, even for relatively simple tasks like the above. That is not to say that Ruby is a messy language, either; it is merely that it is somewhat freer and more forgiving than Python is, and many consider Python's relative purity in this regard a real advantage when it comes to writing clear, easily understandable code.

And Somewhat One of Performance